The present invention relates to a crucible loading/unloading assembly for efficiently moving crucibles onto and from an analyzer furnace.
Analyzers are used in the steel industry inter alia for determining the content of carbon and/or sulfur. Such analyzers include, for example, Model No. CS600 which is commercially available from Leco Corporation of St. Joseph, Mich. In the past, several systems have been designed to provide automatic loading and unloading of crucibles into such furnaces to provide more efficient throughput of samples. One such system is represented in, for example, U.S. Pat. No. 4,238,450. Also, sample combustion boats have been the subject of auto-loading, as shown in U.S. Pat. No. 5,395,586. U.S. Pat. No. 7,402,280 also discloses yet another crucible loading system.
Such automated systems represent a significant advance over manually handling of crucibles and particularly spent crucibles and the potential for injury. However such systems either utilize a sequential multi-step process in which a spent crucible is removed and disposed of and subsequently a new crucible is placed on the induction furnace pedestal for introduction into the furnace or do not handle spent crucibles which must be manually removed. Such systems, although preferable to the manual introduction and removal of crucibles, leave room for improvement to increase the throughput of multiple specimens for analysis. The improved crucible handling system disclosed in Ser. No. 12/055,880 (now Publication No. 2008/0253870 A1) has a shuttle which is fixed to a carriage for moving the shuttle between a crucible loading station and the furnace. When used extensively with ceramic crucibles, the gripping arms of the shuttle can become worn requiring replacement. Also the shuttle-to-carriage electrical and pneumatic connections must accommodate the movement of the shuttle and the carriage. The shuttle can only be removed from the carriage with the use of tools and requires a certain amount time and effort.
There remains a need, therefore, for an improved crucible loading and unloading system which allows quick repair and maintenance.